SR21 The fire performance of unloaded nailed gusset connections for fire-rated timber members (2007)

The fire performance of heavy glulam timber members in portal frame structures is well understood. However, less is known about the fire resistance of their nail-on plywood or steel gusset connections.

Some work has been done overseas to establish standards, codes of practice and design guides in this field. Unfortunately, few of these are readily applicable in New Zealand.

This work forms the first part of a research programme aimed at establishing the appropriate guidelines and providing comprehensive design data for the fire design of these connections in New Zealand. Relevant work has been reviewed and summarised.

The experimental investigation consisted of fire tests on both unprotected and protected unloaded gusset samples as well as other timber samples. The results provide a useful understanding of various design aspects and the relative performance of different protecting materials and arrangements.